Trenching machine



May 30, 1933- c. L. GEORGE TRENCHING MACHINE 1952 3 Sheets-Sheet 1 Filed March 25 May 30, 1933. c. 1 GEORGE TRENCHING MACHINE Filed March 25, 1932 3 Sheets-Sheet 2 May 30, 1933- c. L. GEORGE 1,911,515

TRENCHING MACHINE Filed March 25,1932 s Sheets-Sheet 5 Patented May 30, 1933 UNITED Same GHARLES I}. GEORGE, OF-FINDLAY, OHIO, ASSIGNOR TO THE BUCKEYE 'iTL-A'JL'T'EOIT ITGHER COMPANFL'OF FINDLAY, OHIO, A CORPORATION OLE OHIO TnE-norrme MACHINE v Applicationfiled March 25, 1932, Serial No. 601,209

This invention relates particularly to trenching machines of the wheel-type.

One object of the invention is the provision of .an improved crumber attachment or shoe, which trails the digging wheel to reclaim the crumbs that accumulate behind the wheel buckets and is automatically adjustable in use about the wheel axis as a fixed center to permit it to rise and fall relative to the digging wheel as it follows any changes, from a straight horizontal line, of the trench bottom, and at the same time to maintain a fixed spacing with respect to the wheel axis. This feature of the crumber permits digging to the desired depth much more quickly than is possible with machines employing fixed crumbers, and also has a distinct advantage when excavating trenches where the digging wheel must be frequently raised in order to clear obstructions, such as gas, electric and water lines.

Other objects and advantages will be apparent from the following detailed description and from the accompanying drawings illustrating one embodiment of each of the features of the invention, and in which- Figure 1 is a side elevation of an excavating machine embodying the invention, with the digging wheel in lowered digging position, portions of the machine being omitted. Fig. 2 is a similar fragmentary view of the machine illustrating the action of the crumber as the digging wheel is lowered to depth in a trench digging operation, the

raised position of the wheel and crumber being shown in dotted lines. Fig. 3 is a fragmentary view of the digging wheel and crumber illustrating the manner in which the latter follows a trench bottom as the wheel is raised or lowered from normal depth of digging to clear an obstruction, such as a water line. Fig. 4: is an enlarged side elevation of the crumber and the portion of the frame by which it is carried. Figs. 5 and 6 are cross-sections, respectively, on the lines 5-5 and 6-6 in Fig. 4, and Fig. 7 is an enlarged face view of the crumb-gathering portion of the attachment.

Referring to the drawings, 1 designates r 0 I the maln frame of a trenching machine, carried, in the'present instance, by tractor units 2 of the apron-type, and itself carrying various power and control units common to machines of thistype. i

The customary upright vided at the rear end of the frame 1. The digging wheel 4 is carried in the usual or any suitable manner by the vertically swinging frame 5, which at its forward or inner end is provided with hanger arms 6 pivotally frame 3 is'prosuspended from avblock 7 guided for vertical sliding movements by the upright 3, as well understood in the art. Vertical adjustment of the inner and outer ends of the wheelframe is effected by cables 8 and 9 extending over sheaves at the top of the upright from suitable control means 10 on the'main frame. All of these features of construction are well understood in the art and need not, therefore, be described in detail.

The means for transmitting power to the digging wheel from power means mounted on the main frame 1 comprises across-shaft 11 mounted on the main frame forward of the upright 3 and having suitably controlled driven connection with a power unit 12. This shaft may be termed the drive shaft, as applied to the driving connection between the power unit and digging wheel, and may be the same, both in its mounting and driving, as the corresponding'shaft of the drive means now commonly employed. The shaft 11 has a sprocket-wheel 13 fixed to each end thereof, and also'has a small wheel or disc member 14 mounted thereon between each wheel 18 and the adjacent end of the'casing 1 15in which thesh-aft is mounted. The shaft is longer than the'width of the frame 3 so that the members 13 and 14 are disposed beyond its sides. An arm 16 is mounted at its forward end on each disc member 14 for swinging coaxially with the shaft 11 and has its opposite or rear end provided with a yoke 18. A cross-shaft 19 parallels the shaft 11 and is mounted at its respective end porwith to form a substantially U-shaped frame -tions in suitable bearings or openings pro- 26 at its forward end with the shaft 19 in adjacent relation to the respective yoke end of the arm 16, and has its rear end in bearing engagement with the shaft 24. A sprocketchain 30 connects a sprocket-wheel 29 on each end of the shaft 24 with a respective sprocketwheel (not shown) mounted on the shaft 19 within the forks of the arms 16 and 25.- The shaft 24 has the customary spur-gear driving connection with the rim members of the digging wheel 4. I I

It is apparent with this form of drive for the digging wheel, that the digging wheel frame may be placed in any position of adjustment relative to the main frame without affecting the efiicient driving action of the driving means, and that it eliminates the use of some type of chain slack device customarily employed. 7 V

The crumbing feature of the invention comprises a shoe carried at the lower end of an arcuate arm 36, which extends up through a guide 37 provided at the rear end of the digging wheel frame 5 and is adapted to have free longitudinal sliding adjusting I movements therein. The arm 36 and shoe are disposed at, the rear. peripheral side of the digging wheel 4, and both the curvature of the arm and its arc of adjusting movements are concentric to the axis of the digging wheel, so that the shoe 35 is maintained in fixed spaced relation to the diggin wheel axis irrespective of the position of the shoe relative to the frame.

Thesplane of the bottom surface of the shoe 35 is tangent to a circle defined by the cutting noses of the digging wheel buckets, so that the shoe will ride substantially flat on the bottom of a trench dug by the wheel irrespective of whether or not such bottom definesa straight horizontal course. The shoe rises and falls with respect to the bottom line of the digging wheel to suit the elevation, relative to the wheel bottom, of the portion of the trench bottom on which the shoe rests, and the shoe at the same time maintains a fixed spacing with respect to the wheel axis. This is important in connection with the use of a wheel when digging a course which is inclined to or irregular with respect to a horizontal, such, for instance, as occurs when a diggingwheel-,while digging, is moving down to the desired depth, as indicated in Fig. 2, or when raised and lowered in passing over an obstruction, such, for instance, as a water, gas or electric conduit 38, as shown in Fig.

3. With the type of crumber heretofore eniployed, in which the shoe member thereof maintains a fixed relation to the wheel-carrying frame, it is necessary to have the digging takea more gradual incline in lowering to or raising from a desired digging depth, due to engagement of the stationary shoe with the trench bottom.

The arm 36 of the crumber attachment is, in the present instance, of skeletonv form, being composed of front and back plates 39 curved to the form of the arm and having their edges turned toward each other to form flanges to which respective sets of spacing bars 40 are secured.

The guide 37 for the crumber arm is curved to conform to the curvature of the arm and comprises angle-iron corner guide-strips 41 secured together by suitable cross-pieces 42,

and the guide, as an entirety is carried by the cross-bars 43 and 44 secured tothe rear end of the frame 5 and connecting the transversely' spaced longitudinal members thereof.

The crumber shoe 35 is pivoted to the lower 7 end of the frame near its inner edge, as at 45, and has its rear end adjustably connected to the lower rear end portion of the arm 36 by bolts 46. These bolts, in the present instance, coact with a cross member 47 connecting respective side plates 48 secured to the lower end of the arm. The nose of the crumber comprises a plate 49, which is supported by the forward end of the shoe 35 and extends rearwardly and upwardly to a point where it meets with the curved plate 50 that extends a desired distance up the forward side of the arm. The nose 49 and plate 50 are provided at their side edges with extension plates 51 in boltand slot connection therewith, so that i the effective width of the crumber may be broadened or narrowed to suit the width of the, trench being dug, or the size of the buckets employed on the digging wheel.

It is apparent that in the use of a trenching machine equipped with my crumber attachment, such attachment will automatically rise or fall relative to the digging wheel frame to accommodate itself to the height of the trench bottom relative to the lower edge of the digging wheel and at the same time will maintain a fixed spacing with respect to the digging'wheel axis. It is also apparent that the shoe will maintain an approximately constant parallel relation to the bottom portion of the trench with which it coacts, irrespective of whether or not the wheel is maintaining a constant level in its digging operation, or is moving upward or downward relative thereto. This is illustrated by Figs. 2 and 3. I wish it understoodthat my invention is not limited to any specific construction, arrangement or form of the parts, as it is capable of numerous modifications or changes without departing from the spirit of the claims.

Having thus described my invention, what I claim as new and desire to secure by United States Letters Patent is:

1. In a wheel-type trenching machine, a digging wheel, a carrying frame therefor, and a crumber trailing the digging wheel and adjustably carried by the frame for free arcuate self-adj usting movements coaxial With the wheel axis.

2. In a trenching machine, the combination with a digging Wheel, of a crumber trailing the wheel, and means maintaining the crumber in fixed spaced relation to the wheel axis while permitting free arcuate movements of the crumber about such axis in response to variations in the level of the trench bottom.

3. In an excavating machine, the combination with a digging wheel, of a crumber trailing the wheel and having an arcuate carrying arm, and means engaging the arm to permit it to have free longitudinal gravity-controlled adjusting movements and maintaining the crumber in constant spaced relation to the wheel axis.

4. In an excavating machine, the combination with a digging wheel and the carrying frame therefor, of a crumber trailing the wheel and adapted to ride freely on the bottom of a trench being dug by the wheel, an arcuate carrying arm projecting from the crumber, the arc of which is concentric to the wheel axis, and means carried by the frame for coacting with the arm to guide the armate adjusting movements of the crumber about the wheel axis.

5. In a trenching machine, the combination with a digging wheel and its carrying frame, of an arcuate arm disposed at the rear of the wheel periphery and concentric to its axis, connection between said arm and frame permitting free longitudinal movements of the arm about the wheel axis, a crumber attached to the lower end of the arm and including a shoe adapted to ride freely on the bottom of a trench being dug by the wheel, irrespective of changes in the inclination of the trench bottom.

6. In a trenching machine, a digging wheel, a frame in which the digging Wheel is mounted, and a crumber trailing the digging Wheel and mounted for free and independent gravity-controlled movement up or, down with reference thereto, in response to changes in the inclination of the trench bottom.

In testimony whereof I have hereunto signed my name to this specification.

CHARLES L. GEORGE. 

